1. Field of the Invention
The present invention relates generally to implantable surgical meshes, and more particularly, to implantable surgical meshes that are coated with a lubricious material in such a manner that the coating reduces friction and trauma as the mesh is implanted, and subsequently is substantially eliminated once the mesh is implanted to enable better tissue ingrowth into the mesh.
2. Background Discussion
Implantable surgical meshes have been widely used for a variety of different surgical procedures such as hernia repair, pelvic floor repair, urethral slings for treating incontinence, and many others. In some applications, such as urethral slings, implantation is accomplished without an open surgery, but rather by passing a relatively thin piece of mesh into the body following the path of a needle. One such method for placing a urethral sling is described in detail in U.S. Pat. No. 5,899,909, which is incorporated herein by reference in its entirety. U.S. Pat. No. 5,899,909 discloses a surgical instrument comprising a shank having a handle at one end and connecting means at the other end to receive, one at a time, two curved needle-like elements which are connected at one end to one end of a mesh intended to be implanted into the body. In practice, the mesh is passed into the body via the vagina first at one end and then at the other end at one side and the other, respectively, of the urethra to form a loop around the urethra, located between the urethra and vaginal wall. The mesh is extended over the pubis and through the abdominal wall and is tightened. The mesh ends are cut at the abdominal wall, and the mesh is left implanted in the body. This trans-vaginal procedure is exemplified by the TVT product sold by the Gynecare franchise of Ethicon Inc., a Johnson & Johnson Company, of Somerville, N.J., USA. In this procedure two 5 mm needles pass a PROLENE mesh trans-vaginally and through the abdomen to create a tension-free support around the mid urethra.
When passing the mesh through the body in such a manner, an unprotected mesh, due to its rough abrasive surface will often irritate the surrounding tissue it is being passed through. However, once the mesh is properly placed, it is important to have an exposed mesh structure to promote sufficient tissue ingrowth to thereby secure the mesh in place against future movement. Thus, there are competing interests: on the one hand a desire to reduce as much as possible irritation of surrounding tissue as the mesh is passed into the body, and on the other hand, the desire to have an open mesh structure once properly placed to promote the maximum amount of tissue ingrowth possible.
As described in U.S. Pat. No. 6,491,703 one way in which both objectives have been achieved is by providing a sheath that substantially surrounds the mesh as it is implanted, but then is subsequently removed after the tape is positioned to allow for the proper tissue ingrowth. As described, the sheath must be removed from the respective ends of the tape, and thus there is some degree of tension or movement of the tape following placement, and any such movement is undesirable.
Accordingly, it would be desirable to provide a mesh for implantation into the body, that reduces tissue trauma while inserted, yet provides an open mesh structure following implantation to ensure proper tissue ingrowth.